Color-filter.



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J. A. H. BATT. COLOR FILTER.

APPLICATION FILED Mus, 190e.

Patented Jan. 9, 1912.

LMV Invenlor TES PATENT OFFICE.

JOSEPH ARTHUR HENRY BATT, 0F BROOKLYN, NEW YORK.

COLOR-FILTER.

Specication of Letters Patent.

Patented Jan. 9,1912.

Application filed May 3, 1906. Serial No. 314,944.

ers which carry a liquid or semi-liquid filtering medium. u

Objects of the invention are to provide a filter which is efficient andinexpensive;

which is of simple construction, comprising 'few parts; which has fewjoints thus minimizmg any tendency to leakage or evaporation; and whichmay be manufactured quickly and expeditiously.

. Further objects of the invention are to provide a method for producingsuch a color filter.

These and other objects of the invention will in part be obvious andwill 1n part appear hereinafter.

The invention consists in the novel parts, articles, improvements andcombinations herein described and illustrated.

The accompanying drawings, referred to herein and forming a part hereof,illustrate one embodiment of the invention, the same serving inconnection with the descripvtion herein, to explain the principles ofthe invention.

Of the drawings: Figure 1 represents the parts of a color filterconstructed in accordance with the invention before they are assembled;Fig. 2 is a transverse sectional elevation showing one form of filter;and Fig. 3v is a similar view showing another form thereof.

In photography generally and especially in process reproduction work,which comprises the principal and most important aplication of colorfilters in the art, it is ound desirable to use a liquid or semi-liquidfiltering medium. With such filtering media, however, it has heretoforebeen troublesome and expensive to provide a suitable receptacle orcarrier for the filtering medium. ere carriers are used consisting ofmetal and glass, they are expensive and troublesome to manu acture andare to a great degree subject to leakage and evaporation. Color filtershaving the receptacle or carrier for the filtering medium glass areknown to the art but the said receptacles are made up of a large numberof pieces, involving a close fitting of joints and careful applicationof a suitable adhesive for holding them together. Such receptacles arealso expensive and troublesome to manufacture and are likewise subjectto leakage and evaporation by reason of the large number of jointsnecessary.

The present invention contemplates providing a color lter in which thereceptacle for the filtering medium consists of but two or threemembers. It will be manifest that, bv reason of the fewness of the partsand the a sence of joints, it will be a slmple matter to assemble theparts of the color filter; that there will be but little opportunity forleakage or evaporation; that but little labor will be required to sealthe filter against leakage or evaporation; and that the color filter maybe quickly and inexpensively manufactured. The invention furthercontemplates having the parts of such shape that there are no joints incontact with the filtering medium except where extended flatsurfacesmeet, joints of such character not requiring close fitting and grinding.

Referring to the embodiment illustrated herewith by way of example, itwill be seen from Fig. 3 of the drawings that an integral plate 1 of asuitable material, which may be glass, is shown so shaped as to form theentire side walls and one face of the receptacle for the filteringmedium a'. Another form of such plate is shown in Figs. 1 and 2 of thedrawings and is indicated by the reference numeral 2. In the form ofsuch plate last mentioned, an internal portion thereof is cut away toform the side walls of the receptacle for the filtering medium. The sidewalls of the receptacle for the fltering medium in this case also areformed by the integral plate 2. In either case it will be understoodthat the plate provides an imperforate wall for the receptacle for thefiltering medium. With the form shown in Fig. 3 the plate 1 is itself ofa light-transmitting material; with the form shown in Figs. 1 and 2,however, the plate 2 may be of any suitable material for holding theliquid or semi-liquid filtering medium. With the form shown in Fig. 3 ofthe drawings, a light-transmitting plate 3 is used to form a cover forthe receptacle after the made entirely of ai LO! UIA.

filtering medium has been placed therein, said light-transmitting platebeing vusually of glass. lVith the form shown in Figs. l and of thedrawings two such plates are used and are indicated by the referencenumerals 4 and 5.

It will be seen that, as hereinbefore indi cated, the few number ofparts and the shape and disposition of the parts are such as to bringvery few joints in contact with the filtering medium and such joints arenot edge joints but occur Where flat and comparatively extended surfacescome together. The advantage of this in preserving the filtering mediumunchanged will be obvious. However, in order to still further precludethe possibility of evaporation, or other changes due to the atmosphere,one feature of the invention contemplates applying to the external edgesof the assembled plates a suitable means for rendering the joints of theplate air-tight. For this purpose a sealing material, such as paraffinor wax, may be used, a layer of such material being indicated in thedrawings by the reference numeral 6. It will be necessary after theplates are assembled to hold them rmly together, and in the presentembodiment there is provided for this purpose a flexible binder 7 aboutthe edges of the plates, the said binder being of any suitable material,such as heavyr paper or fabric. The binder will further serve as aprotection for the layer of sealing material 6.

One process of producing a filter such as is included by this inventioncomprises the taking of a plate of suitable material, such as a glassplate, and removing a portion within such plate to form a receptacle forthe filtering medium. The removed portion may extend entirely throughthe plate or not as desired. The filtering material is then placedwithin the receptacle in the case where the receiving portion does notextend entirely through the plate. In the case where the entire interiorportion of the plate has been out away, the plate with the cutawayportion is placed upon one of the covering plates and the filteringmedium is then placed within the receptacle so formed. The remainingplate is then placed so as to cover the opening, and while the parts arefirmly held together to exclude the air, a suitable sealing material isapplied to the edges of the three plates and the plates are boundtogether, as by the flexible strip hereinbefore described.

From all the foregoing it will be understood that a color filter hasbeen provided which realizes the objects of invention and the advantageshereinbefore set forth, together with other objects and advantages.

WhatI do claim as my invention and desire to secure by Letters Patent,is:

1. A color filter including in combination a single member so shaped asto form an imperforate wall for the receptacle for the filtering medium,and light-transmitting mens for completely closing the said receptac e.

2. A color` filter including in combination asingle member so shaped as'to forlnan imperforate wall about the filtering medium, and opposedlight-transmitting surfaces forming with the said member a closedreceptacle for thefiltering medium.

3. A color filter including in combinatio a plate having an internalportion thereof cut away to form an imperforate wall for the receptaclefor the filtering medium, and a light-transmitting plate on each side ofsaid first-named plate to form the faces of the receptacle.v

4. A color filter including in combination a plate having an internalportion thereof cut away to form an imperforate wall for the. receptaclefor the filtering medium, a light-transmitting plate on each side ofsaid first-named plate to form the faces of the receptacle, and meansfor rendering the joints of the said plates air-tight.

5. A color filter including in combination a plate of glass having aportion within the plate cut away to form an imperforate wall for thereceptacle for the filtering medium, a glass plate on each side of saidfirst-named plate, a sealing material for rendering the edge joints ofthe said plates air-tight, and a binder placed about the edges of thesaid plates for holding them together.

6. A color filter including in combination a plate of glass having aportion within the plate cut away to form an imperforate wall for thereceptacle for the filtering medium, a glass plate on each side of saidfirst-named plate, and a binder placed about the edges of the saidplates for holding them together.

7. A color filter including in combination a non-porous, fluidcontaining member presenting an imperforate surface to the containedfluid, and a non-porous, light-transmitting member for closing the fluidopening.

8. A color filter including in combination a member so shaped as to forman imper-v forate wall for the receptacle for the filtering medium, andlight-transmitting means for completely closing the said receptacle.

9. A color filter including in combination the filtering fluid, a plateof vitreous material having an internal portion thereof cut away to forman imperforate wall for the receptacle for the filtering fluid, and avitreous, light-transmitting plate fitting againstsaid first-mentionedplate.

10. A color filter including in combination the filtering fluid, a plateof vitreous material having an internal portion cut away therethrough toform an imperforate wall for the filtering fluid, a vitreous light ssilos

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(WwW- transmitting plate on each side of said rstmentioned plate to formthe light-transmitting faces of the receptacle.

ll. A color lter including in combination the filtering liuid, a plateof vitreous material having flat smooth sides and an internal portioncut therethrough to form an imperforate Wall for said filtering fluid,said Hat, smooth sides extending about said out out portion, a Hatsmooth plate of glass on either side of said first-mentioned plate, to'form the light transmitting Walls of the tiuid containing receptacle,the sides of the three plates lying against each other in close contact.

l2. A color filter including in combination the filtering iuid, a plateof vitreous material having fiat smooth sides and an inan imperforateWall for said ltering fluid, said flat, smooth sides extendin about saidcut out port-ion, a flat, smooth p ate of glass on either side of saidirst mentioned plate to form the light transmitting Walls of thefluid-containing receptacle, the sides of the three plates lying againsteach other in close contact, and a binding strip folded about andadherent to the edges of said three plates.

14. A color filter including in combination the filtering iuid, a plateof vitreous material having fiat, smooth sides and an internal portioncut therethrough to form an imperforate wall for said ltering iuid, saidflat, smooth sides extendin about said cut out portion, a Hat, smooth pate of glass on either side of said iirst mentioned plate to form thelight transmitting walls of the fluid containing receptacle, the sidesof the three plates lying against each other in close contact, a sealingmaterial sealing the adjoining edges of the three plates, and a bindingstrip folded about and adherent to the edges of said three plates.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

JOSEPH ARTHUR HENRY HATT.

Witnesses:

J oHN D. MORGAN, CLARA PHILLIPS.

Copies of this patent may be obtained for ve cents each, by addressingthe "Commissioner of Patent,

Washington, D. C.

